Transmission point indication in coordinated multi-point system

ABSTRACT

Embodiments of the present disclosure describe devices, methods, computer-readable media and systems configurations for transmission point indication in a coordinated multipoint (CoMP) system. A user equipment (UE) may receive common reference signal (CRS) parameters associated with individual base stations of a CoMP measurement set. The UE may also receive a transmission point index corresponding to a first base station of the CoMP measurement set that is scheduled for communications with the UE. A mapping module of the UE may produce a physical downlink shared channel (PDSCH) mapping pattern based on the CRS parameters associated with the scheduled base station.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 15/061,839, filed Mar. 4, 2016, entitled “TRANSMISSION POINTINDICATION IN COORDINATED MULTI-POINT SYSTEM,” which is a continuationof U.S. patent application Ser. No. 13/997,588 with 371(c) filing dateof Sep. 12, 2013, entitled “TRANSMISSION POINT INDICATION IN COORDINATEDMULTI-POINT SYSTEM,” which is national phase entry under 35 U.S.C. § 371of International Application No. PCT/RU2012/000235, filed Mar. 29, 2012,entitled “TRANSMISSION POINT INDICATION IN COORDINATED MULTI-POINTSYSTEM,” which claims priority to U.S. Provisional Patent ApplicationNo. 61/556,109, filed Nov. 4, 2011, entitled “ADVANCED WIRELESSCOMMUNICATION SYSTEMS AND TECHNIQUES.” The entire content anddisclosures of which are hereby incorporated by reference in theirentireties.

FIELD

Embodiments of the present invention relate generally to the field ofcommunications, and more particularly, to transmission point indicationin wireless communication networks.

BACKGROUND

Coordinated multipoint (CoMP) systems have been developed in order toimprove various operational parameters in wireless networks. In CoMPsystems that utilize dynamic point selection (DPS), a transmission pointmay be selected from a plurality of nodes (e.g., base stations) of aCoMP measurement set. The transmission point may be dynamically assignedby a serving node. However, since the user equipment does not know theidentity or characteristics of the current transmission point, commonreference signal (CRS, also referred to as cell-specific referencesignal) positions across all nodes in the CoMP measurement set must bemuted.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will be readily understood by the following detaileddescription in conjunction with the accompanying drawings. To facilitatethis description, like reference numerals designate like structuralelements. Embodiments are illustrated by way of example and not by wayof limitation in the figures of the accompanying drawings.

FIG. 1 schematically illustrates a wireless communication network inaccordance with various embodiments.

FIG. 2 is a configuration table in accordance with various embodiments.

FIG. 3 is a flowchart illustrating a transmission point indicationmethod that may be performed by a user equipment in accordance withvarious embodiments.

FIG. 4 is a flowchart illustrating a transmission point indicationmethod that may be performed by a base station in accordance withvarious embodiments.

FIG. 5 schematically depicts an example system in accordance withvarious embodiments.

DETAILED DESCRIPTION

Illustrative embodiments of the present disclosure include, but are notlimited to, methods, systems, and apparatuses for transmission pointindication in a coordinated multi-point (CoMP) system of a wirelesscommunication network.

Various aspects of the illustrative embodiments will be described usingterms commonly employed by those skilled in the art to convey thesubstance of their work to others skilled in the art. However, it willbe apparent to those skilled in the art that alternate embodiments maybe practiced with only some of the described aspects. For purposes ofexplanation, specific numbers, materials, and configurations are setforth in order to provide a thorough understanding of the illustrativeembodiments. However, it will be apparent to one skilled in the art thatalternate embodiments may be practiced without the specific details. Inother instances, well-known features are omitted or simplified in ordernot to obscure the illustrative embodiments.

Further, various operations will be described as multiple discreteoperations, in turn, in a manner that is most helpful in understandingthe illustrative embodiments; however, the order of description shouldnot be construed as to imply that these operations are necessarily orderdependent. In particular, these operations need not be performed in theorder of presentation.

The phrase “in some embodiments” is used repeatedly. The phrasegenerally does not refer to the same embodiments; however, it may. Theterms “comprising,” “having,” and “including” are synonymous, unless thecontext dictates otherwise. The phrase “A and/or B” means (A), (B), or(A and B). The phrase “A/B” means (A), (B), or (A and B), similar to thephrase “A and/or B”. The phrase “at least one of A, B and C” means (A),(B), (C), (A and B), (A and C), (B and C) or (A, B and C). The phrase“(A) B” means (B) or (A and B), that is, A is optional.

Although specific embodiments have been illustrated and describedherein, it will be appreciated by those of ordinary skill in the artthat a wide variety of alternate and/or equivalent implementations maybe substituted for the specific embodiments shown and described, withoutdeparting from the scope of the embodiments of the present disclosure.This application is intended to cover any adaptations or variations ofthe embodiments discussed herein. Therefore, it is manifestly intendedthat the embodiments of the present disclosure be limited only by theclaims and the equivalents thereof.

As used herein, the term “module” may refer to, be part of, or includean Application Specific Integrated Circuit (ASIC), an electroniccircuit, a processor (shared, dedicated, or group) and/or memory(shared, dedicated, or group) that execute one or more software orfirmware programs, a combinational logic circuit, and/or other suitablecomponents that provide the described functionality.

FIG. 1 schematically illustrates a wireless communication network 100 inaccordance with various embodiments. Wireless communication network 100(hereinafter “network 100”) may be an access network of a 3rd GenerationPartnership Project (3GPP) long-term evolution (LTE) network such asevolved universal mobile telecommunication system (UMTS) terrestrialradio access network (E-UTRAN). The network 100 may include a basestation, e.g., enhanced node base station (eNB) 104, configured towirelessly communicate with user equipment (UE) 108.

At least initially, the eNB 104 may have an established wirelessconnection with the UE 108 and may operate as a serving node within aCoMP measurement set. One or more additional eNBs of the network 100,e.g., eNBs 112 and 116, may also be included within the CoMP measurementset. eNBs 112 and 116 may be configured to facilitate wirelesscommunication with the UE 108 through coordination with the eNB 104. Theone or more additional eNBs may be collectively referred to as“coordinating nodes.” An eNB may transition between coordinating andserving node roles.

The serving node and coordinating nodes may communicate with one anotherover a wireless connection and/or a wired connection (e.g., a high-speedfiber backhaul connection).

The eNBs may each have generally the same transmission powercapabilities as one another or, alternatively, some of the eNBs may haverelatively lower transmission power capabilities. For example, in oneembodiment the eNB 104 may be a relatively high-power base station suchas a macro eNB, while the eNBs 112 and 116 may be relatively low-powerbase stations, e.g., pico eNBs and/or femto eNBs.

The UE 108 may include a communications module 120, a mapping module124, and memory 132 coupled with one another at least as shown. Thecommunications module 120 may be further coupled with one or more of aplurality of antennas 132 of the UE 108 for communicating wirelesslyover network 100.

The UE 108 may include any suitable number of antennas. In variousembodiments, the UE 108 may include at least as many antennas as anumber of simultaneous spatial layers or streams received by the UE 108from the eNBs, although the scope of the present disclosure may not belimited in this respect. The number of simultaneous spatial layers orstreams may also be referred to as transmission rank, or simply rank.

One or more of the antennas 132 may be alternately used as transmit orreceive antennas. Alternatively, or additionally, one or more of theantennas 132 may be dedicated receive antennas or dedicated transmitantennas.

In various embodiments, the communications module 120 may receive commonreference signal (CRS) parameters associated with individual basestations of the CoMP measurement set (e.g., eNBs 104, 112, and/or 116).For example, the CRS parameters may include an index, a number of CRSantenna ports, and/or a CRS frequency shifts associated with each basestation of the CoMP measurement set. These parameters, which may varyamong the base stations of the CoMP measurement set, may be used by thecommunications module 120 to accurately and efficiently identifyrelevant CRS transmissions.

FIG. 2 is a CRS configuration table 200 with various CRS parameters inaccordance with some embodiments. The CRS configuration table 200(hereinafter “table 200”) may be stored in memory 128 and accessible bythe mapping module 124. The transmission point index may be a valuesubsequently used in the communication of which node is the scheduledtransmission point. The CRS antenna ports may be the antenna ports,either virtual or physical, of the base station over which CRStransmissions are transmitted. In some embodiments, the number of CRSantenna ports may be 1, 2, or 4. The CRS frequency shift may be acell-specific frequency shift (e.g., in terms of number of subcarriers)that may be used to avoid constant collocation of reference signals fromdifferent cells. In some embodiments, the CRS frequency shift may be 0,1, 2, 3, 4, or 5.

In some embodiments, the CRS parameters may further include informationrelated to a quantity and/or location of resource elements (e.g.,sub-carriers and/or OFDM symbols) of the OFDM frame that are dedicatedto control information and/or multicast/broadcast single frequencynetwork (MBSFN) information for the individual base stations of the CoMPmeasurement set. The resource elements used for control informationand/or the MBSFN subframes may not include the CRS.

In some embodiments, the UE 108 may store the received CRS parameters inmemory 128. The UE 108 may keep the CRS parameters so long as the UE 108is associated with the CoMP measurement set, and/or for another suitablelength of time.

Subsequent to the configuration of the table 200 with the appropriateCRS parameters, the communications module 120 may receive a transmissionpoint index corresponding to a base station of the CoMP measurement setthat is scheduled for communication with the UE 108 (e.g., according toa dynamic point selection (DPS) protocol). The mapping module 124 maythen access the CRS parameters that correspond with the receivedtransmission point index and produce a physical downlink shared channel(PDSCH) mapping pattern based on the CRS parameters of the scheduledbase station. The PDSCH mapping pattern may be used for subsequentcommunications with the scheduled base station. For example, the PDSCHmapping pattern may identify locations (e.g., resource elements) of CRSsin an orthogonal frequency division multiplexing (OFDM) frametransmitted by the scheduled base station. The resource elements maycorrespond to one or more sub-carriers and/or OFDM symbols in the OFDMframe. Accordingly, the PDSCH mapping pattern may be specificallytailored to the scheduled base station.

In some embodiments, the CRS parameters may be transmitted to the UE 108by the serving base station (e.g., eNB 104). In some embodiments, theCRS parameters may be transmitted to the UE 108 via radio resourcecontrol (RRC) signaling. The CRS parameters may be transmitted duringconfiguration of the CoMP measurement set for the UE 108 (e.g., as partof a CoMP measurement set configuration protocol). The CoMP measurementset configuration protocol may also include configuration of channelstate information reference signal (CSI-RS) parameters and/or an uplinkcontrol channel for channel state information (CSI) feedback.Accordingly, the UE 108 may receive and/or transmit one or more CSI-RSparameters and/or uplink control channel parameters as part of the CoMPmeasurement set configuration protocol.

In various embodiments, the communications module 120 may receive thetransmission point index via physical layer signaling. For example, inone embodiment, the transmission point index may be included in downlinkcontrol information (DCI), e.g., via a downlink control channel. Thismay allow for dynamic communication of relevant CRS parameterscontemporaneously with the dynamic switching of the various transmissionpoints in a DPS protocol. The DCI may further include other parametersfor scheduling communications between the UE 108 and one or more basestations.

The transmission point index may identify the base station (e.g.,transmission point) of the CoMP measurement set that is scheduled forcommunications with UE 108 (e.g., for transmission on the PDSCH). Forexample, the transmission point index may include one or more bitscorresponding to the scheduled base station. In some embodiments, asmall number of bits may be needed to identify the scheduled basestation. For example, if the CoMP measurement set includes two basestations, the transmission point index may include one bit, and/or ifthe CoMP measurement set includes three or four base stations, thetransmission point index may include two bits. In other embodiments, thetransmission point index may include the same number of bits regardlessof the number of base stations included in the CoMP measurement set. Itwill be apparent that other suitable mechanisms of identifying thescheduled base station may be used.

In some embodiments, the transmission point index may be transmitted bythe scheduled base station. For example, eNB 104 may send UE 108 atransmission point index identifying eNB 104 as the scheduled basestation. In other embodiments, the transmission point index may betransmitted by a different base station from the scheduled base station.For example, eNB 104 may send UE 108 a transmission point index thatidentifies eNB 112 as the scheduled base station.

The mapping module 124 may use the transmission point index to identifythe CRS parameters (e.g., from memory 128) corresponding to thescheduled base station. The mapping module 124 may produce a PDSCHmapping pattern based on the CRS parameters for the scheduled basestation. For example, the quantity of CRS antenna ports of the scheduledbase station may be used to identify resource elements (e.g.,sub-carriers and/or OFDM symbols) of the OFDM frame that are dedicatedto CRS transmission. The CRS frequency shift may be specific to thescheduled base station, and may be used to identify the CRS locations(e.g., resource elements) of the OFDM frame for the scheduled basestation.

The communications module 120 may then receive one or more transmissionsfrom the scheduled base station, the transmission including an OFDMframe having a plurality of CRSs. The CRSs may be arranged in the OFDMframe according to the PDSCH mapping pattern.

In various embodiments, the transmission point (e.g., scheduled basestation) may be dynamically assigned. The UE 108 may receive additionaltransmission point indexes if the identity of the scheduled base stationchanges and/or periodically at any suitable timing interval.

eNB 104 may include a communications module 136 and a CoMP managementmodule 140 coupled with one another at least as shown. Thecommunications module 136 may be further coupled with one or more of aplurality of antennas 152 of the eNB 104. The communications module 136may communicate (e.g., transmit and/or receive) with one or more UEs(e.g., UE 108). In various embodiments, the eNB 104 may include at leastas many antennas as a number of simultaneous transmission streamstransmitted to the UE 108, although the scope of the present disclosuremay not be limited in this respect. One or more of the antennas 152 maybe alternately used as transmit or receive antennas. Alternatively, oradditionally, one or more of the antennas 152 may be dedicated receiveantennas or dedicated transmit antennas. The CoMP management module 140may transmit (e.g., via the communications module 136), CRS parametersassociated with the individual base stations of the CoMP measurement setas described above.

Though not shown explicitly, the eNBs 112 and 116 may includemodules/components similar to those of the eNB 104.

The transmission point indication as described herein may allow the UE108 to know which base station of the CoMP measurement set is scheduledas the transmission point for the UE 108 (e.g., according to a DPSprotocol). Additionally, the UE 108 may know the CRS parametersassociated with the scheduled transmission point, and may thus produce aPDSCH mapping pattern that is tailored specifically to the scheduledbase station.

In DPS systems, demodulation reference signal (DM-RS) antenna ports maybe dynamically assigned to base stations for transmission. The basestation may apply the same pre-coding scheme (e.g., spatial and/ormultiple input multiple output (MIMO) pre-coding scheme) to the DM-RS ason the PDSCH. Accordingly, the UE may not need to know the identity ofthe transmission point in order to receive DM-RS to decode the PDSCHtransmission. However, different base stations may have differentquantities of CRS ports and/or may have a CRS frequency shift that isdependent on the identity of the base station. Accordingly, the CRSconfiguration (e.g., arrangement of CRSs within the PDSCH transmission)may change from one base station to another.

In prior CoMP systems, to enable DPS the CRS positions for all basestations in the CoMP measurement set may be muted in the PDSCH. However,this approach requires high overhead due to unused resources in thePDSCH. Additionally, the muting of CRS locations may adversely affectlegacy UEs (e.g., UEs that are not capable of CoMP communications) thatconduct interference measurements on CRS. For example, a legacy UEconducting interference measurements on a CRS position may not receivethe interference from other base stations (since the other base stationsmute the CRS locations). Accordingly, the legacy UE may produceinterference measurements that do not accurately measure theinterference from the other base stations. This may lead to incorrectmodulation and coding decisions, which may in turn lead to increasederror and/or throughput drops for the legacy UE.

In contrast, the transmission point indication described herein allowsthe UE to know the CRS parameters of the base station scheduled fortransmission to the UE. The UE may thus produce a PDSCH mapping patternthat is tailored specifically to the scheduled base station. Thetransmission by the base station may not need to mute the CRS locationsof other base stations in the CoMP measurement set. This may saveoverhead from unused resources for all UEs associated with the basestations of the CoMP measurement set (e.g., UEs that are capable of CoMPcommunications and legacy UEs that are not capable of CoMPcommunications). Additionally, the transmission point indication may notimpact the interference measurements of legacy UEs on CRS.

FIG. 3 illustrates a transmission point indication method 300 inaccordance with various embodiments. The transmission point indicationmethod 300 may be performed by a UE (e.g., the UE 108). In someembodiments, the UE may include and/or have access to one or morecomputer-readable media having instructions stored thereon, that, whenexecuted, cause the UE to perform the method 300.

At block 304, the UE may receive CRS parameters via RRC signaling. TheCRS parameters may be associated with individual base stations of a CoMPmeasurement set that includes a plurality of base stations. In someembodiments, the CRS parameters may include a quantity of CRS antennaports and/or a CRS frequency shift of the individual base stations ofthe CoMP measurement set. The UE may receive the CRS parameters as partof a CoMP configuration protocol. The CoMP configuration protocol mayalso include configuring CSI-RS parameters and the uplink controlchannel for CSI-RS feedback. Accordingly, the UE may also receive one ormore CSI-RS parameters and/or uplink control channel parameters via RRCsignaling, in addition to the CRS parameters. The UE may store thereceived CRS parameters in memory.

At block 308, the UE may receive a transmission point index via DCI. Thetransmission point index may correspond to a scheduled base station ofthe CoMP measurement set that is scheduled for communications with theUE (e.g., scheduled as the transmission point for the UE).

At block 312, the UE may produce a PDSCH mapping pattern based on thereceived CRS parameters associated with the scheduled base station. ThePDSCH mapping pattern may be used for subsequent communications betweenthe UE and the scheduled base station. For example, the UE may receive atransmission on the PDSCH from the scheduled base station that includesan OFDM frame. The OFDM frame may include a plurality of CRSs arrangedwithin the frame according to the PDSCH mapping pattern.

FIG. 4 illustrates a transmission point indication method 400 that maybe performed by a base station (e.g., eNB 104) in accordance withvarious embodiments. The base station may be the serving node of a CoMPmeasurement set that includes a plurality of base stations.

At block 404, the base station may transmit CRS parameters to a basestation via RRC signaling. The CRS parameters may include a quantity ofCRS antenna ports and/or a CRS frequency shift of the individual basestations of the CoMP measurement set. The base station may transmit theCRS parameters as part of a CoMP configuration protocol. The CoMPconfiguration protocol may also include configuring CSI-RS parametersand the uplink control channel for CSI-RS feedback.

The base station may be pre-configured to know the CRS parameters forthe plurality of base stations of the CoMP measurement set.Alternatively, or additionally, the base station may receive the CRSparameters for one or more base stations from the respective basestation(s). In some embodiments, the base station may store the CRSparameters for the plurality of base stations in memory.

In some embodiments, a CoMP management module may determine which basestations are included in the CoMP measurement set. The CoMP managementmodule may be included in the base station and/or in another location(e.g., in the core network including the base station). In someembodiments, the CoMP measurement set may be different for different UEswithin a cell covered by the base station.

At block 408, the CoMP management module may determine which basestation of the CoMP measurement set will be the scheduled base stationfor the UE. The determination of the scheduled base station may be madebased on any suitable factors, such as channel conditions, relativeloads on the base stations, relative power of the base stations, and/orother factors.

At block 412, the base station may transmit a transmission point indexto the UE via DCI. The transmission point index may identify a scheduledbase station of the CoMP measurement set that is scheduled as thetransmission point for the UE. The scheduled base station may thentransmit PDSCH signals to the UE. In some embodiments, the transmissionpoint index may be transmitted by the scheduled base station. In otherembodiments, the transmission point index may be transmitted by anotherbase station that is not the scheduled base station.

The UE 108 described herein may be implemented into a system using anysuitable hardware and/or software to configure as desired. FIG. 5illustrates, for one embodiment, an example system 500 comprising one ormore processor(s) 504, system control logic 508 coupled with at leastone of the processor(s) 504, system memory 512 coupled with systemcontrol logic 508, non-volatile memory (NVM)/storage 516 coupled withsystem control logic 508, a network interface 520 coupled with systemcontrol logic 508, and input/output (I/O) devices 532 coupled withsystem control logic 508.

The processor(s) 504 may include one or more single-core or multi-coreprocessors. The processor(s) 504 may include any combination ofgeneral-purpose processors and dedicated processors (e.g., graphicsprocessors, application processors, baseband processors, etc.).

System control logic 508 for one embodiment may include any suitableinterface controllers to provide for any suitable interface to at leastone of the processor(s) 504 and/or to any suitable device or componentin communication with system control logic 508.

System control logic 508 for one embodiment may include one or morememory controller(s) to provide an interface to system memory 512.System memory 512 may be used to load and store data and/orinstructions, for example, for system 500. System memory 512 for oneembodiment may include any suitable volatile memory, such as suitabledynamic random access memory (DRAM), for example.

NVM/storage 516 may include one or more tangible, non-transitorycomputer-readable media used to store data and/or instructions, forexample. NVM/storage 516 may include any suitable non-volatile memory,such as flash memory, for example, and/or may include any suitablenon-volatile storage device(s), such as one or more hard disk drive(s)(HDD(s)), one or more compact disk (CD) drive(s), and/or one or moredigital versatile disk (DVD) drive(s), for example.

The NVM/storage 516 may include a storage resource physically part of adevice on which the system 500 is installed or it may be accessible by,but not necessarily a part of, the device. For example, the NVM/storage516 may be accessed over a network via the network interface 520 and/orover Input/Output (I/O) devices 532.

System memory 512 and NVM/storage 516 may respectively include, inparticular, temporal and persistent copies of mapping logic 524. Themapping logic 524 may include instructions that when executed by atleast one of the processor(s) 504 result in the system 500 implementinga mapping module, e.g., mapping module 124, to perform the PDSCH mappingoperations described herein. In some embodiments, the mapping logic 524,or hardware, firmware, and/or software components thereof, mayadditionally/alternatively be located in the system control logic 508,the network interface 520, and/or the processor(s) 504.

Network interface 520 may have a transceiver 522 to provide a radiointerface for system 500 to communicate over one or more network(s)and/or with any other suitable device. The transceiver 522 may implementcommunications module 120. In various embodiments, the transceiver 522may be integrated with other components of system 500. For example, thetransceiver 522 may include a processor of the processor(s) 504, memoryof the system memory 512, and NVM/Storage of NVM/Storage 516. Networkinterface 520 may include any suitable hardware and/or firmware. Networkinterface 520 may include a plurality of antennas to provide a multipleinput, multiple output radio interface. Network interface 520 for oneembodiment may include, for example, a wired network adapter, a wirelessnetwork adapter, a telephone modem, and/or a wireless modem.

For one embodiment, at least one of the processor(s) 504 may be packagedtogether with logic for one or more controller(s) of system controllogic 508. For one embodiment, at least one of the processor(s) 504 maybe packaged together with logic for one or more controllers of systemcontrol logic 508 to form a System in Package (SiP). For one embodiment,at least one of the processor(s) 504 may be integrated on the same diewith logic for one or more controller(s) of system control logic 508.For one embodiment, at least one of the processor(s) 504 may beintegrated on the same die with logic for one or more controller(s) ofsystem control logic 508 to form a System on Chip (SoC).

In various embodiments, the I/O devices 532 may include user interfacesdesigned to enable user interaction with the system 500, peripheralcomponent interfaces designed to enable peripheral component interactionwith the system 500, and/or sensors designed to determine environmentalconditions and/or location information related to the system 500.

In various embodiments, the user interfaces could include, but are notlimited to, a display (e.g., a liquid crystal display, a touch screendisplay, etc.), a speaker, a microphone, one or more cameras (e.g., astill camera and/or a video camera), a flashlight (e.g., a lightemitting diode flash), and a keyboard.

In various embodiments, the peripheral component interfaces may include,but are not limited to, a non-volatile memory port, a universal serialbus (USB) port, an audio jack, and a power supply interface.

In various embodiments, the sensors may include, but are not limited to,a gyro sensor, an accelerometer, a proximity sensor, an ambient lightsensor, and a positioning unit. The positioning unit may also be partof, or interact with, the network interface 520 to communicate withcomponents of a positioning network, e.g., a global positioning system(GPS) satellite.

In various embodiments, the system 500 may be a mobile computing devicesuch as, but not limited to, a laptop computing device, a tabletcomputing device, a netbook, a smartphone, etc. In various embodiments,system 500 may have more or less components, and/or differentarchitectures.

In some embodiments, an apparatus, e.g., a UE, is described thatincludes a communications module configured to receive CRS parametersassociated with individual base stations of a CoMP measurement setincluding a plurality of base stations, and to receive a transmissionpoint index corresponding to a first base station of the CoMPmeasurement set. The UE may further include a mapping module coupledwith the communications module and configured to produce a PDSCH mappingpattern based on the CRS parameters associated with the first basestation.

In some embodiments, the communications module may be further configuredto use the CRS parameters associated with the first base station forsubsequent communications with the first base station.

In some embodiments, the CRS parameters and transmission point index maybe received from a second base station of the CoMP measurement set. Inother embodiments, the CRS parameters may be received from the secondbase station, and the transmission point index may be received from thefirst base station.

In some embodiments, the CRS parameters may be received via radioresource control (RRC) signaling. The transmission point index may bereceived via physical layer signaling (e.g., the transmission pointindex may be included in downlink control information). The CRSparameters may include a number of CRS antenna ports and/or a CRSfrequency shift of the individual base stations. In some embodiments,the CRS parameters may further include information related to OFDMresource elements dedicated to control information for the individualbase stations. In further embodiments, the CRS parameters may furtherinclude MBSFN information for the individual base stations. In someembodiments, the CRS parameters may be received as part of aconfiguration protocol for the CoMP measurement set. The configurationprotocol may further include configuring CSI-RS parameters and uplinkcontrol channel parameters for communications between the user equipmentand one or more base stations of the CoMP measurement set.

In some embodiments, the communications module may be further configuredto receive a transmission from the first base station, the transmissionincluding an OFDM frame having a plurality of CRSs. The CRSs may bearranged within the frame according to the PDSCH mapping pattern.

In some embodiments, the apparatus may further include memory configuredto store the received CRS parameters.

In some embodiments, an apparatus, e.g., a base station (such as aneNB), is described to include a communications module, and a CoMPmanagement module coupled to the communications module and configured totransmit, to a UE via the communications module, CRS parametersassociated with individual base stations of a CoMP measurement setincluding a plurality of base stations.

In some embodiments, the CoMP management module may be furtherconfigured to transmit a transmission point index to the UE. Thetransmission point index may correspond to a first base station of theCoMP measurement set scheduled to communicate with the UE. In someembodiments, the scheduled base station may transmit the transmissionpoint index. In other embodiments, a base station that is not thescheduled base station may transmit the transmission point index.

In some embodiments, the base station may be a serving node of the CoMPmeasurement set configured to manage communications between the UE andthe plurality of base stations of the CoMP measurement set.

In some embodiments, the CRS parameters may include a number of CRSantenna ports and/or a CRS frequency shift of the individual basestations. The CRS parameters may be transmitted by radio resourcecontrol signaling. The transmission point index may be transmitted tothe UE in a downlink control information transmission. In someembodiments, the CRS parameters may be transmitted as part of aconfiguration protocol for the CoMP measurement set. The configurationprotocol may further include configuring channel state informationreference signal (CSI-RS) parameters and uplink control channelparameters for communications between the UE and one or more basestations of the CoMP measurement set.

In various embodiments, a method is disclosed that includes receiving,by a UE via radio resource signaling, CRS parameters associated withindividual base stations of a CoMP measurement set including a pluralityof base stations; receiving, by the UE via a downlink controlinformation transmission, a transmission point index corresponding to afirst base station of the coordinated multipoint measurement set; andproducing a PDSCH mapping pattern based on the CRS parameters associatedwith the first base station.

In various embodiments, one or more computer-readable media aredisclosed that have instructions, stored thereon, that, when executedcause a user equipment to receive CRS parameters associated withindividual base stations of a CoMP measurement set including a pluralityof base stations, the CRS parameters including a number of CRS antennaports of the individual base stations; receive a transmission pointindex corresponding to a first base station of the coordinatedmultipoint measurement set; and produce a PDSCH mapping pattern based onthe CRS parameters associated with the first base station.

Although certain embodiments have been illustrated and described hereinfor purposes of description, a wide variety of alternate and/orequivalent embodiments or implementations calculated to achieve the samepurposes may be substituted for the embodiments shown and describedwithout departing from the scope of the present disclosure. Thisapplication is intended to cover any adaptations or variations of theembodiments discussed herein. Therefore, it is manifestly intended thatembodiments described herein be limited only by the claims and theequivalents thereof.

What is claimed is:
 1. A user equipment (UE) comprising: communicationscircuitry to: receive, via radio resource control (RRC) signaling from afirst transmission point, a plurality of individual common referencesignal (CRS) parameter sets; receive a physical downlink control channel(PDCCH) that includes a 2-bit value to indicate one of the individualCRS parameter sets that is to be used by the UE to decode a physicaldownlink shared channel (PDSCH), wherein the PDCCH is received from asecond transmission point that is different from the first transmissionpoint, and wherein the PDSCH is to be transmitted by the secondtransmission point; and mapping circuitry coupled to the communicationscircuitry, the mapping circuitry to: identify the indicated individualCRS parameter set, from the plurality of individual CRS parameter sets,based on the 2-bit value; and decode the PDSCH transmitted by the secondtransmission point based on the identified individual CRS parameter set.2. The UE of claim 1, wherein the mapping circuitry is further todetermine a PDSCH resource element (RE) mapping pattern based on theidentified individual parameter set, and wherein the PDSCH is decodedbased on the PDSCH RE mapping pattern.
 3. The UE of claim 1, wherein theindividual CRS parameter sets of the plurality of CRS parameter setsinclude a number of CRS antenna ports and a CRS frequency shift.
 4. TheUE of claim 3, wherein the individual CRS parameter sets further includeinformation related to a quantity or location of REs that are dedicatedto multicast/broadcast single frequency network (MBSFN) information. 5.The UE of claim 4, wherein the individual CRS parameter sets furtherinclude one or more channel state information reference signal (CSI-RS)parameters.
 6. The UE of claim 3, wherein the individual CRS parametersets further include a transmission point index, and wherein the 2-bitvalue corresponds to the transmission point index of the indicatedindividual parameter set.
 7. The UE of claim 1, wherein the individualCRS parameter sets are associated with different transmission points ofa Long Term Evolution (LTE) network that are included in a coordinatedmultipoint (CoMP) measurement set.
 8. The UE of claim 1, wherein the2-bit value is included in downlink control information (DCI) of thePDCCH, and wherein the PDCCH is detected after the receipt of theplurality of parameter sets via the RRC signaling.
 9. One or morenon-transitory computer-readable media having instructions, storedthereon, that when executed cause an evolved Node B (eNB) to: transmit,to a user equipment (UE), a physical downlink control channel (PDCCH)that includes a 2-bit value to indicate an individual common resourcesignal (CRS) parameter set from among a plurality of parameter sets thatwere transmitted to the UE by another eNB, wherein the indicatedindividual CRS parameter set is to be used by the UE to decode aphysical downlink shared channel (PDSCH); and transmit, to the UE, thePDSCH based on the indicated individual parameter set.
 10. The one ormore computer-readable media of claim 9, wherein, to transmit the PDSCHbased on the indicated individual parameter set, the eNB is to providethe PDSCH with a PDSCH resource element (RE) mapping pattern accordingto the indicated individual parameter set.
 11. The one or morecomputer-readable media of claim 9, wherein the individual parametersets include a number of CRS antenna ports and a CRS frequency shift.12. The one or more computer-readable media of claim 11, wherein theindividual parameter sets further include information related to aquantity or location of REs that are dedicated to multicast/broadcastsingle frequency network (MBSFN) information.
 13. The one or morecomputer-readable media of claim 11, wherein the individual parametersets further include one or more channel state information referencesignal (CSI-RS) parameters.
 14. The one or more computer-readable mediaof claim 11, wherein the individual CRS parameter sets further include atransmission point index, and wherein the 2-bit value corresponds to thetransmission point index of the indicated individual parameter set. 15.The one or more computer-readable media of claim 9, wherein the CRSparameter sets are associated with different transmission points of aLong Term Evolution (LTE) network.
 16. The one or more computer-readablemedia of claim 9, wherein the 2-bit value is transmitted after thetransmission of the plurality of CRS parameter sets.
 17. An apparatus tobe employed by a user equipment (UE), the apparatus comprising: meansfor receiving, via radio resource control (RRC) signaling, a pluralityof parameter sets, wherein individual parameter sets of the plurality ofparameter sets include a number of common reference signal (CRS) antennaports and a CRS frequency shift; means for receiving, after theplurality of parameter sets are received, downlink control information(DCI) that includes a 2-bit value to indicate one of the individualparameter sets that is to be used by the UE to decode a physicaldownlink shared channel (PDSCH); means for identifying the individualparameter set indicated by the 2-bit value; and means for decoding thePDSCH based on the identified individual parameter set.
 18. Theapparatus of claim 17, further comprising means for determining a PDSCHresource element (RE) mapping pattern based on the identified individualparameter set, and wherein the means for decoding the PDSCH is to decodethe PDSCH based further on the PDSCH RE mapping pattern.
 19. Theapparatus of claim 17, wherein the individual parameter sets furtherinclude: information related to a quantity or location of REs that arededicated to multicast/broadcast single frequency network (MBSFN)information; and one or more channel state information reference signal(CSI-RS) parameters.
 20. The apparatus of claim 17, wherein theindividual parameter sets further include a transmission point index,and wherein the 2-bit value corresponds to the transmission point indexof the indicated individual parameter set.
 21. The apparatus of claim17, wherein the means for receiving the plurality of parameter sets isto receive the plurality of parameter sets from a first transmissionpoint and wherein the means for receiving the DCI is to receive the DCIfrom a second transmission point that is different from the firsttransmission point.
 22. An apparatus to be employed by an evolved Node B(eNB), the apparatus comprising: means for transmitting, to a userequipment (UE) via radio resource control (RRC) signaling, a pluralityof parameter sets, wherein individual parameter sets of the plurality ofparameter sets include a number of common reference signal (CRS) antennaports, a CRS frequency shift, and a transmission point index; means fortransmitting, after the plurality of parameter sets are transmitted,downlink control information (DCI) that includes a 2-bit value thatcorresponds to the transmission point index of one of the individualparameter sets to indicate that the individual parameter set is to beused by the UE to decode a physical downlink shared channel (PDSCH); andmeans for modulating the PDSCH based on the indicated individualparameter set.
 23. The apparatus of claim 22, further comprising meansfor determining a PDSCH resource element (RE) mapping pattern based onthe indicated individual parameter set, and wherein the means formodulating the PDSCH is to modulate the PDSCH based further on the PDSCHRE mapping pattern.
 24. The apparatus of claim 22, wherein theindividual parameter sets further include: information related to aquantity or location of REs that are dedicated to multicast/broadcastsingle frequency network (MBSFN) information; and one or more channelstate information reference signal (CSI-RS) parameters.
 25. Theapparatus of claim 22, wherein the parameter sets are associated withdifferent transmission points of a Long Term Evolution (LTE) network.